Lifting mechanism



March 5, 1935. l, VON K HOTT LIFTING MECHANISM Filed March '7, `1954 ullllllllllh/Is TTRNEY Patented Mar. 5, 1935 y y' UNITED STATES 1,993,447 A n n LIFTING MEonANIsM Ion lVon Kert Hott, Dayton,` Ohio, assignorgto Y VThe Sl'oyce-Cricllandr Company, Dayton, Ohio,

a corporation of Ohio Y f Applieatiennarch 7, 1934, serial No. 714,444

2o claims; (ci. 2me-89pV This invention relates to a'lifting mechanism and more particularly toa liftingvmechanism of the .type commonly employed for elevating an automobile to permit greasing, or otherwise servicing, the underneath partsfthereof.V Such a lift y y y Y vention; Fig. 2 is a plan view of a free wheel lift is ordinarily hydraulically operated and comprises a cylinder embedded in the ground, a ram mounted inthe cylinder and a structure carried by the ram for supporting the automobile. The ram is usually rotatable in the cylinder, thus permitting the supportingk structurev to rotate. Under some conditions the rotation of the supportingstructure is desirable but when, as is now customary, a Series of lifts are arranged side by yside within a building, the rotation of the supautomobile is driven to a position above the rails itis not always exactly parallel with the rails andthe latter must be moved to a position sub.

stantially parallel with 1 the automobile before they will properly engage the axles. A hydraulicallyoperated lift of this kind is usually retained in its'elevated position by closing the valve which controls the admission and discharge of the fluid to and from thecylinder and should there bea break in the oil line, as for example if the packing should blow out, the lift would be permitted to suddenly drop, which might result in injury to an operator under the automobile orto the automobile itself.

One object of the present invention is to provide a lifting mechanism having means for controlling the rotation of the supporting structure.

A further object of the invention is to provide a lifting mechanism in which the controlling mechanism for the supporting structure will be of such a character as topermit of a limited rotary movement only ofthe supporting structure.

A further object of theinvention is to providel such a lift with a safety device which will automatically control the downward movement of the ram independently of the oil line.

A further object of the invention is to provide a lifting mechanism in which Ythe control for the rotary movement of the supportingVA structure gle mechanism.

' Other'objects vof the invention'will appear as theapparatus is described in detail. Y

In "the accompanying drawing Fig. 1 isa side elevation, partly in sectiony and partly broken away, of an automobile lift'embodying my inwithportions of the rails broken away; Fig. 3 is an" elevation of, the combined rotation controlling device and safetyy deviceiooking in the direction opposite that shownin Fig. 1; and Fig. 4 is ar detail' view ofthe pivoted locking device.

In theA drawing I have, illustrated rone embodi- -ment of my invention and have shown'the same appliedA to an automobile liftiof a well known type. lits here shown, this lift comprises acylinder 5 embeddedA in the ground, `the term groundl being usedy to linclude a floor, pavementor the like;v Mounted Within this cylinder lisa ram 6 on the upper end of which is mounted a supporting structurecomprising a cross member 7 and'parallel rails 8 carried by the cross member. In applying my invention to a lift of thisjkind I `provide at one side of the cylinder and Yram 'a' vertically' movable device whichv is connected with theram in such a manner that it will have vertical movement substantially in unison therewith and this vertically movable device is ,so lconnected with the supporting structure that it will control the rotatory movement of the latter, and the safety device acts on the vertically movable device to lock the same against down- Ward movement until such time as the safety vdevice is moved to an inoperative position by the operator. y

PreferablyV the Vvertically movable device is in the form of a rod,'which may be of any suitable character, eitherV in one part or a plurality of parts, As here shown,` the rod 9 is tubular in form and is mounted in a, vertical guideway 10 which is formed by embedding a tube in the ground alongside of and parallel with the cylinder. The rod has free sliding movement in the guideway but is held against lateralV movement. The upper end of the rodY is connected with the supporting structure in suchfa manner as `to control the rotary or swinging movement of the supporting structure and this connection. may take any'suitable form. Ashere shown it is of such a character that the supporting structure Y may be held against all rotary movement or may be permitted to have a limited-'rotary movement. Itis not necessary, however, that the connecting' means Vshould have both characteristics in'one lift, but when the lift is of the runway type', in which the Wheels ofthe vehicle are supported on Gil the rod is provided at its upper end with a part 1l having a lateral recess 12 facing toward'the ram and this part is shown as a separate casting rigidly secured to theupper end ofthe tubular rod 9 and forming in effect a part of that rodi" The supporting structure is provided with a laterally extending part which, projects into the recess 12 and this part is here shown. as a plate 13 having a depending flange 14 which is welded, lor otherwise rigidly secured to, the transverse member 7 of the. supporting structure. VThe transverse member 7 and the rod bothbeing held against lateral movement it will beapparent that when the plate `13 has been inserted in the recess 12 it will be retained therein and the rod'l will be caused to move vertically with the ram.'k By making the casting 11 separate from the rod 9 it can be placed in proper engagement with the plate 13 and then secured to the body Yof the rod and, as here shown, the casting is `provided with a vshank 15 which extends into'therupper end of the tubular rod 'and' may be secured therein in any suitable manner, as by means of a pin 16. When the supporting structure is -to be held against all rotatory movement the part 11 of the rod is rigidly securedft'o the part or plate 13 of the supporting structure and for this purpose an operable device has been provided forclamping together, or otherwise rigidly connecting, the parts 11 and 13. As here shown, a.sc`rew17is mounted in the part 11 above Athe recess 12 and when tightened down will clamp the plate' 13 firmly against the part 11, thelower wall of the recess`12`being here shown as provided with an upwardly extending Vprojection orlpad 18 in line with the screw 7, so that the plate 13 is rigidly clamped against the screw and the pad. The plate is preferably of a width somewhat greater than the width of the part 11 of the rod, and by loosening the screw the supporting structure may, within certain limits, be adjustedabout .its axis.

In order that a limited rotatory movement may be imparted to the supporting'structure the rod l and the supporting structure are provided with spaced stops so arranged that when the supporting structure has been rotated to the desired limit these stops will engage one with the other and positively prevent further movement. In the present construction theplate '13 carried by the supporting structure is provided at its sides with upright bars or lugs 20 which extend above the recess 12 in the part 11 of the rod and are spaced apart a distance somewhat Vgreater than the width of that portion of the part 11 which is arranged between the lugs 20.l When these stops are provided the screw 17, or other fastening means, may be moved to an inoperative position, or entirely omitted, and the stops will prevent the supporting structure from being rotated in either direction to an objectionable extent. Whenit is desired to prevent vall rctatory movement the screw is tightened down, withthe parts 11 and 13 in their` properly adjusted positions, thus, rigidly connecting the parts one to the other.

If the rod and the ram are rigidly and permanently connected one to the other it is necessary' either for the rod to be absolutely parallel with the ram or for the rod to have a slight tilting movement to prevent binding. The tilting of the rod is not desirable and true parallelism is dilicult to attain in an installation of this kind. When the connecting parts, 1,1 and 13, can have a slight lateral movement with relation one to the other true parallelism is not essential because the connecting parts will automatically accommodate themselves to any slight divergence in the lines o; movement of the rod andthe ram.

Y Mounted near the upper end of the guideway l0 and preferably nearthe surface of the ground is a locking device adapted to engage the rod 9 and hold the same against downward movement, therebypreventing the downward movement of the ram. This locking device is of such a character that when in its operative position it will function ,automatically to prevent downward movement of the rod but it may be moved to and retained in aninoperative position to permit of the downward movement of the rod and of the ram. Preferably means are vprovided whereby the locking device will be automatically restored to its operative position as the ram nears the lower limit of its movement. This locking device may take various forms and may engage the rod in` any suitable manner which will control its downward movement, but preferably the engagement is'such as topositively prevent the downward movement of the rod. v As here shown, the rod 9 is provided near its lower end with arecess 21 which is shown inthe form of an aperture in the wall ofthe tubular rod. The locking device is in the form of aV pawl 22 pivotally mounted on a bracket 23 with its axis transverse tol the rod. This pawl is provided with a nose 24 adapted to enter the recess 21 in the rod when the latter is in its'elevated position. So long as the usual locking mechanism for the ram is operative little or no weight will be imposed upon the pawl 22 but should the usual lockingmechanism become inoperative the pawl will support the entire weight ci the ram and of the supporting structure, together with the loadthereon. I have also shown the rod 10 with a second or intermediate recess 25 adapted to be engaged by the pawl 22 to support the lift in an intermediate position, as when work isbeing done on the wheels, and the rod is also provided with a third recess 26 near the upper end thereof intov which the nose of the pawl 22 Ymay extend when the ram is in its lowermost position. The locking device or pawl 22 is, of course, movable into and out'o its operative position and it is provided with means for automatically retaining the same in the position to which it has been moved. As here shown, this means comprises anr arm 27 projecting v inwardly from the upper end of the pawl and'constituting a weight which tendsto move the pawl toward the rod and to cause the nose thereof to enter the recesses when ,these are brought into line therewith by the movement of the ram. The arm 27 also extends outwardly beyond the axis of the pawl and has its 'endturned downwardlyyas shown at 28, so that it may be'readily'engaged by the foot of the operator and the pawl moved about its axis to its inoperative position.' The pawl and the parts carried thereby'are so arranged that whenV the pawl is in its operative position the center ofl gravity will be on the inner side of the axis of. the pawl and it will thus be automatically retained in itsoperativeposition, but ywhen the pawl is moved to its inoperative position the center of gravity is shifted to the outer side of theaXis andthe pawl will be held in its inoperative position lwiththe armY 2'7 inclined upwardly and inwardly, as shown in dotted lines in Fig. 3. lThis armis arranged at one side of and extends across 4theupper. portion. of the rod 9 but it lies in the path of the plate 13 f on the'supporting structure, .sothat when the isin its. lowermostposition the nose of. the pawlr will enter, the recess 26 and asv the'rod-moves upwardly the nose will be forced out ofthe recess and will ride over thesurface of the rod, but themovement imparted ,to the pawl will not be suicient to shift, fthe center of gravity rto the outer side of the axis. Consequently when the lift has been moved lto its elevated position the nose of the pawl` willenter the recess 21,` or 25,V

as the case may be, and will he in a position to positively prevent the downward movement of the ram. When the lift isrto be lowered the operator moves the looking device to its inoperative lpositionLvin whichposition it remains Yuntil the ram been lowered andthe plate v13has restored the locking device to its operative position. Thus the'locking deviceisautomatically restored to operative position independently of anyaction on the part cf the operator and whenever the lift is elevated this locking device is operative. --fWhile I have shown and described one embodiment cf my` invention I wish it to be understood that I do Vnot. desire to be limited to thev details thereof as ,various modifications may occur to a personslilled in the art. Y'

I-Iaving now fully described my invention, what I claim as new and desire to securer by Letters Patent, is:v Y d .Y .A l *d l. Ina lifting;mechanism comprising a Vram and a supporting structurev carried bysaid ram,

a A,device mounted alongside of and-connected with said ram fcr'vertical movement therewith and having ,means'tol limit the rotary movement of said supporting structure, and means-to secure said supporting structure against rotary movement when it has been adjusted to a selected position Within said limit. d

2. In a lifting mechanismfcomprising a ram and a supporting structure carried by said ram, a Vrod arranged at one sidev of said'ram, connected with said supporting structure for, vertical movement therewith and held against lateral movement, cooperating parts carried by said rod and said/supporting structure and'arranged to interrupt the rotary movement of said supporting structure after a predetermined rotary Vmovement has been imparted thereto, and operable means associated with said'parts to holdsaid supporting structure against all ro tary movement. 3. In *aV lifting mechanism comprising a ram v and a supporting structure carried by said ram,

a vertically movable rod arranged at one side of said ram and held against lateral movement, and interengaging members carried respectively by said rod and said supporting structure to cause said rod to move Avertically with said supporting structure, one of said members having parts arranged on opposite sides of the other member to v toits operative position.

limit'the rotary .movement of said supporting structure.' v

'4. In a.,.lifting mechanism comprising a Yram and a lsupporting structure carried by said ram,

`a vertically movable rod arranged at one side of said'ram and held against lateral movement, said rod having' at its upper, enda part .provided with a lateral recess, said supportingstructure having a part extending into said recess, means for rigidly connecting said parts one to the other to holdV said supportingstructure against rotary movement, and stops carried by one of said parts to engage. the other of said parts and limit the ro'- tary movementof said supporting structureiiwhen said connecting means is inoperative.

15. In a lifting mechanism comprising av ram and a supporting structure carried by said ram,.a

Vvertic'ally movable rod arranged at one side of said ram and held against lateral movement, said rod having at its upper end a part-provided with a lateral recess,l said supporting structure ,having a part extending into said recess, and stops `carried byfonegofnsaid parts and arranged to engage the, other of said vparts and limit the rotary vmovement-of said supporting structure,

,Y 6. In a lifting mechanism comprising a ram and a supporting lstructure carried Yby v said ram, a verticallymovable rod arranged alongside ofsaid ram and held againstnlateral movement, means for connecting said rod with said support-v ing structure in such aV manner that it will move vertically therewith Aand will controlthe rotary movement of said supporting structure, `and a lockingdcvice movable into and Yout of engagement withfsaid rod to hold thesame against downward movement, said locking devicer having means to hold the same normallyfin engagement with said rod. ,A r Y f. i 7. In a lifting mechanism comprising a ram and a. supporting structure carried by said ram',

a rod arrangedat one side of said ramand'connected with said` ram for vertical movement therewith,y and a device mounted on a fixed supportlfor movement into engagement with lsaid rod tocontrol the downwardmovement of said ram. 8.In a lifting mechanism comprising a ram and a supporting structure carried vby said ram,

a rodarranged at one side of said ram and conf ative position, and means controlled by the downward movementof said ram to restore the sameA 9. Ina lifting mechanism comprising-a ram' ,andy a supporting structure carried by said ram,

land a supporting structure carried by said ram,

a rod arranged at one side of said ram and connected with said ram for vertical movement therewith,'said rod having a recess, a pivoted locking device having a part arranged to enterk tol Said recess and lock saidrod against downward movement and having a gravity operated part movable acrossthe pivotal axis of said device to hold the same in either its operative position or its inoperative position, and a part carried'by,

said ram to engage the last-mentioned'- part of saidV device when `the latter is in its inoperative position and. restore said device to its operative position when said ram moves to its lowermost position.

11."In a lifting mechanism comprising a cylinder embedded in the ground, a ram in said cylinder and a supporting structure carried by Said ram, a guideway in the ground-parallel with said cylinder, a rod slidably mounted in said guideway, means for "connectingsaid'rod with said supportingstructure for vertical movement therewith, a locking device to engage said rod'and hold the same against downward movement, said locking 'device having means to retain the same in either its operative position or its inoperative position, and means controlled by the downward movement of said ram to move said locking device to its operative position.

12. In a lifting' mechanism comprising a cylinder embedded in the ground, a ram in said cylinder andv a'supporting structure carried by said ram, a guideway in the ground'parallel with said cylinder, a rod slidably mounted in' said guideway, means for connecting said rod with vsaid supporting structure for vertical movement therewith, a locking device to engage said rod and hold the same against downward movement, said locking device having means to retain the same in either its operative position or its inoperative position, means controlled by the downward movement of said ram to move said locking device to its operative position, said rod and said supporting structure having parts cooperating tocontrol the rotary movement of said supporting structure.

13. In a lifting'mechanismV comprising a ram and a supporting 'structure carried by said ram, a vertically movable rod arranged at one side of said ram and held against lateral movement, said rod having at its upper end a part spacedv laterally from said supporting structure and provided with a lateral recess facing said structure, said supporting structure having Va part extending into said recess, and means rcarried by said parts to retain the last mentioned part in said recess and thereby control the rotarymovement of said supporting structure. j

14. In a lifting mechanism comprisinga ram,

and a supporting structure carried by said ram,'

15.4 In a lifting mechanism comprising a ram,

and a supporting structure carried by said ram, a

vertically movable rod arranged alongside of said ram and held against lateral movement, means forl connecting saidrrod with said supporting structure in suchfa manner that it will move vertically.' therewith .and will control the rotary movement of said supporting structure, and a locking device mounted for movement into and out of apposition t'o engage said rod and lock said ramin an `elevated position, .said locking device being. held against bodily movement in the direction of movement of said rod.

16..In a lifting mechanism comprising a ram and a supporting structure vcarried by said ram, a device mounted alongside of and connected with said ram for vertical-movement therewith, a second device mounted independently of said vertically movable device and cooperating therewith to'prevent the'downward movement of said ram, said seconddevice being movable to an inoperative position to permit said ram to be lowered, and means controlled by the downward movement of said ram to automatically restore'said second device to its operative position. l

17. In a lifting mechanism, comprising a ram and asupporting structure carried by said ram, a Ydevice mounted alongside of and connected with said ram for vertical movement therewith, and a device pivotally mounted on a fixed support for movement into and out of Ya position to engage a part of said vertically movable device and h'old said ram against downward movement.

18. In a lifting mechanism comprising a ram and a supporting structure "carried by said ram, a device mounted alongside of and connected with said rain for vertical movement therewith,

and a device pivotally mounted on a xed support for movement intoY and out lof a lposition to engage a part of said vertically movable device and hold said ram against downward movement, said pivoted device having meansVv controlled by the movement thereof to retain the same either in said position or out of said`position. Y

19. VIn an automobile lift comprising a ram and an elongated supporting structure carried by said ram to engage the axles of an automobile, a device mounted alongside of and adjacent to said ram for vertical movement therewith and having means to control the rotary movement of said supporting structure, said controlling means being arranged to permit a limited rotatory movement of said supporting structure to aline the same with said automobile and to positively limit said rotatory movement in both directions.

20.V In an automobile lift comprising a ram and an elongated supporting structure carried by said ram and adapted to engage the axles of an automobile, a rod arranged at one side of and adjacentl to said ram, connected with said supporting structure for `vertical movement therewith and held against lateral movement, and cooperating parts carried by said rod and said supporting structure to positively limit the rotatory movement of said structure, said` parts being so arranged that sufficient movement may be imparted to said supporting structure to aline the same with said automobile before it engages said axles.

ION VON KERT HOTT. 

